Rotary reamer



A. BOYNTON ROTARY REAMER March 18, 1930.

Filed April 1'74 1925 2 Sheets-Sheet l W INVENTOR vilexa/wzderfi @Oyvzfiin WITNESSES :iw 654/ am Q4,

ATTORNEYS March 18, 1930. 4 BOYNTON 4 1,750,953

ROTARY REAMER Filed April 17, 1925 2 Sheets-Sheet 2 Iii/O. 6.

WITNESSES 1 On "if/L7 9 Jlaxcuuefi Bop m7? ATTORNEYS Patented Mar. 18,1930 ALEXANDER BOYNTON, OF SAN ANTONIO, TEXAS ROTARY REAMEB Applicationfiled April 17, 1925. Serial No. 23,879.

This invention relates to a method of reaming oil wells or the like andalso to an improved rotary reamer adapted for use in carrying out themethod. The improved rotary reamer is of the type forming thesubjectmatter of my co-pending application, filed Oct. 23, 1924, SerialNo. 745,456.

The object of the invention resides in the provision of a novel methodof reaming oil wells which has many of the.adv antages of an ordinarydownwardly progressing reaming operation while avoiding thedisadvantages and objectionable features thereof.

Another object of the invention resides in the provision of a rotaryreamer which has at least twice the efiiciency of the ordinary reamer inthat the reamer blade with which the reamer is equipped has two cuttingedges both of which are used in the reaming operation so that it is notnecessary to withdraw the reamer from the well and replace the same inthe well after renewing or sharpening the reamer blades with but halfthe frequency required with a single edged blade.

A further object resides in the provision of a novel means for drainingfrom the drill stem the fluid or fluid used to control the v reamerblade.

A still further object resides in the provision of a novel fluidpressure actuated means for controlling the action of the reamer blade.Another object resides in the provision of novel means for washing outthe cuttings, said means being of such a character as to incidentallyserve to keep the operator advised of the character and progress of thereaming action.

Other objects and advantages reside in certain novel features of theconstruction, arrangement and combination of parts which will behereinafter more fully described and particularly pointed out in theappended claims, reference being had to the accompanying drawingsforming a part of this specification, and in which:

Figure 1 isa view in central longitudinal vertical section showing arotary reamer constructed in accordance with the present invention, thereamer blade being shown in elevation;

Figure 2 is a view similar to Figure 1 but showing the reamer blade in asubstantially horizontal position; I

Figure 3 is a view in horizontal section on the line 33 of Figure 1;

Figure 4 isa diagrammatic view illustrating the method of reaming out awell;

Figure 5 is a detail perspective view of the reamer blade;

Figure 6 is a similar view of a similar form of blade for use in cuttingthrough and milling away casing;

Figure 7 is a perspective view of the pivot pin employed for mountingthe blades of Figures 5 and 6 on the reamer casing;

Figure 8 is a detail view in elevation of the piston and the rackemployed for controlling the movement of the reamer or cutting blade,the sleeves of the piston being removed;

Figure 9 is a detail view partly in elevation and partly in section andshowing a modified form of reamer blade rock reamer especially adaptedfor use in reaming rock or hard formations, and 1 Figure 10 is a view inelevation of the rock reamer shown in Figure 9, and

Figurell is a View showing the shank of the blade of Figs. 9 and 10 inelevation, the rollers and felt washers being removed and showing thehead in section.

Referring to the drawings, 1 designates the lower end of a hollow rotarydrill stem which is of conventional construction. It is to be understoodthat this invention is intended for use in conjunction with the usualequipment or machinery employed in the rotary drilling of oil, gas, orwater wells, the usual rotary being employed for rotating the drill stemand the standard equipment 7 ordinarily employed being utilized forraising and lowering the drill stem. The usual pumps employed on rotaryrigs are also utilized for the purpose of supplying water or otherliquid or fluid under pressure down through the hollow rotary drill stemto the reamer constituting the present invention. These'instrumentalities are so widely employed and so well known 'in the artof drilling as to need no illustration here.

To the lower end of the hollow rotary drill stem 1 a reamer assemblyconstituting the present invention, and designated generally by 2, isconnected, a sub 3 being employed for connecting the reamer assembly tothe drilling stem 1.

The reamer assembly 2 comprises a cylindrical casing 4 which isinternally machined to provide a cylinder. The lower end of the casing 4is provided with a transverse slot or 0pening5 which extends out throughone side of the casing and which also extends down through the lower endthereof. The slot 5 is formed between internal enlarge ments of thecasing and the upper ends of these enlargements present a shoulder 5. Areamer blade, designated generally at 6, is provided and has a head 7disposed in the opening 5 and pivotally connected to the lower end ofthe casing by a pivot pin 8. The reamer blade 6 has a shank 9 providedwith two cutting edges, one being designated at 10 and the other beingdesignated at 11. The reamer blade 6 normally hangs in the positionshown in Fig. 1 and its approach toward one portion of the casing 4 islimited by means'of a stud-bolt 12 threaded into the blade andengageable with the casing 4, the

bolt 12 providing an adjustable abutment or stop. ,With the arrangementshown the blade 6 is pivoted for swinging movement about an axisextending transversely of the reamer casing and may hang verticallydownwardly from and in alignment with the casingor.

may be moved to a horizontal position at right angles to the casing, asshown in Figure 2.

Fluid pressure operated means is provided for swinging the reamerblade 6from the position shown in Fig. 1 to the position shown in Figure 2 andthis means includes a piston,,designated generally at 13 operating inthe cylinder of the casing 4 and having a pair of heads 14 and 15connected by a neck portion 16. The fluid under pressure is suppliedfrom the ordinary pump down through the hollow drill stem to thecylinder in the casing 4 and is usually the ordinary washing fluid. Thehead 15 has an integral extension 17 provided with teeth 18 on'itsstraight portion and teeth 18* on its curved portion, the extension 17and its teeth 18 and 18 constituting a rack. The teeth 18 and 18 meshwith the teeth 19 formed on the head 7 of the blade 6. When the piston13 has been moved down the cylinder provided in the casing 4 as far asit may be, it abuts the shoulder 5., the teeth 18* as well as certain ofthe-teeth 18 are meshed with the teeth 19, the'portion 15 of the head 15of the piston is engaged with the portion 6 of the head 6 of the reamerblade, and the head 6 of the reamer blade also engages an abutment 20provided by the portion of the casing 4 which lies at the upper end ofthe slot or opening 5, whereby the reamer blade is firmly supported in ahorizontal position.

sleeve has three such grooves therein, the

grooves of each sleeve being spaced equidistant from each other. Thesegrooves tend to prevent sticking and burring of the piston against thecylinder. In the event the piston should stick or freeze in the cylinderthe continuity of the stuck or frozen section would be broken by thegrooves. Particles of the piston which might stick or freeze to the wallwould be scraped from the wall by the movement of the piston, and thegrooves would afford a convenient pocket or receptacle in which suchparticles would collect, thereby removing them as wedges between pistonand wall. I

The head 14 is provided with a plurality of lengthwise openings 25.These'openings 25 permit the fluid or liquid'under pressure to pass intothe space between the pistons at all times and when the piston 13 iselevated in the cylinder, as shown in Fig. 1, a certain amount of thisfluid or liquid may escape through a small exhaust port 26. When thepiston 13 has been forced down in the cylinder to the position shown inFig. 2, the fluid or liquid under pressure forcibly discharges through arelatively large exhaust port 27 also provided in the cylinder casing 4.

In reaming a well with the reamer described and in accordance with thenovel method proposed by this invention, the reamer is lowered down intothe well to the bottom of the formation to be reamed-out. During thelowering operation, the blade 6 occupies the position shown in Fig. 1.With the reamer at the bottom of the formation to be reamed out it isrotated and fluid pressure is supplied to the top of the piston 13 so asto force the piston 13 down in the cylinder in the casing 4 and swingthe reamer blade 6 outwardly and upwardly as the entire assemblyrotates. During this operation the cutting edge 11 is active and byvirtue of this operation the cavity shown at A in Fig. 4 is formed. Thecavity A is not completely formed until the reamer blade 6 has beenforced up to a substantially horizontal position by the action of thefluid pressure. During the time that the reamer blade is moving from avertical to a horizontal position a certain amount of washing fluid isbeing supplied through the port 26. When the reamer blade approaches ahorizontal position the port 26 begins to be closed by the piston head14 while the piston head 13 begins to uncover the ort 27. When thereamer blade 6 has final y reached a substanmoves downward,

tially horizontal position, as shown in Fig. 2, the port 26 is closedand the port 27 is 0 en and the maximum amount of washing flui or liquidis supplied for carrying away the cuttings.

An important feature of the invention resides in the fact that the pumpsignals to the operatorthe exact position of the blade. Port 26 is openwhen the reaming operation begins. Port 26 is a small port. As pistonjust as port 27 begins to open. Port 27 being about twice as large asport 26, the pump begins to exhaust faster and continues to run fasteruntil port 27 is wide open. Port 27 is wide open just before piston .andblade engage, with blade in horizontal position.

on the reaming blade reaches the horizontal position, the rotary beginsto spin, that is, runs much faster because the reaming arm can go nohigher and therefore ceases to out. There is, therefore, at this point adouble signal given to the operator. First, the pump is wide open, andsecond, the rotary spins. Then in reaming downward until the cavitybelow is reached, the pump continues to remain wide open but the rotarylabors until the lower cavity is reached, when the rotary begins againto spin. Therefore,

by observing the action of the pump and the action of the rotary, thetool practically talks to the operator, telling him in unmistakableterms the exact position of the blade at all times.

After the cavity A has been formed the drill stem is elevated to bringthe reamer assembly about three or four feet above the cavity A and theprocess just described is repeated to form a cavity B. When the cavity Bhas been formed the reamer blade 6 is held in a horizontal position andwhile so held the drill stem is lowered while being rotated so as to cutaway the material between the cavities 1A and B by a downwardlyprogressing reaming action. This downwardly progressing reaming actionbrings the cutting edge 10 of the reamer blade into .play and does notutilize the cutting edge 11.- The downwardly progressing reeaming actionjust described is had without the serious disadvantadge of the drillstem wabbling and flopping around because the drill stem has a fairlyood bearing in a nearly adjacent unreamed hole, and does not extend fora substantial portion of its length unsupported through a reamed hole.Moreover, the casing 4 has a forward extension 4* which extends inadvance of the tool at one side of the same and which has its outersurface slightly beveled, as shown to advantage in Figs. 1 and 2. Thisforward extension gives the tool a bearing in advance of the portion ofthe well that is being reamed out during the downwardly progressingreaming action. The beveled or rounded off external formation of theforport 26 begins to close ward extension precludes the possibility ofthe bearing surface provide by the extension being worn oil b therotation of the tool. After the cavity has been formed the drill stem israised to bring the reamer assembly three or four feet above the cavityB and the operation just described is repeated and may be repeatedthereafter as often as is necessary to ream out the formation.

It is to be understood here that the invenwell or the like whichconsists in forming a cavity at the bottom of the formation to be reamedby an outwardly and upwardly proessive reaming action. More particularlyhis step of the method consists in forming this cavity by swinging areamer blade outwardly and upwardly to a substantially horizontalposition. A second step in the method consists in similarly forming asecond cavity a short .distance above the first cavity, the second stepbeing accomplished by raising the reamer and repeating the actiondescribed in connection with the formation of the first cavity. Afterthe second cavity has been formed the final step consists in removingthe material between the cavities by a downwardly progressing reamingaction. Specifically the downwardly progressing reaming action consistsin holding the reamer blade in a substantially horizontal position afterthe second cavity has been reamed and in utilizing the reamer bladewhile so held to remove the material between the cavities by rotatingthe drill stem on which the reamer blade is carried and feeding thedrill stem downwardly.

The reamer-blade 6 hereinbefore described is especially adapted for usewith soft formations. When hard rock formations are encountered thereamer blade shown in Figs. 9, 10 and 11 of the drawings, and designatedgenerally at 50, is preferably employed. The reamer blade includes ahead 51 having teeth 52 adapted to mesh with the teeth 18 of the rack ofthe piston. The reamer blade 50 also includes a shank 53 which has anexternally reduced extension 54 of tapered form, the reduced extensionbeing threaded into a correspondingly formed socket 55 provided in thehead 51. Set screws 56 are threaded into the head 51 and engage thethreaded extension 54 to hold the shank against accidental displacementfrom its head. The shank 53, is of stepped formation and is machined toprovide bearing surfaces 58,59 and 60 for roller cutters 61, 62 and 63,respectively. The roller cutter 61 abuts the head 51. the roller cutter62 is positioned between shoulders 64 and 65 formed on the shank 53 bythe steps thereof and the roller cutter 63 is positioned between theshoulder 65 and an annular fastening nut 66 engaged with the shankaccommodated in a recess in the roller cutter and held in position byset tion involves a novel method of reaming a 'verse oil passages screws67. A felt washer 68 is interposed washer 70 of similar form in crosssection extends around the shoulder 65 and is interposed between theroller cutters 62 and 63. A flat washer 71 is interposed between the nut66 and the inner wall of the recess in the roller cutter 63 in which thenut 66 is accommodated. These felt washers prevent the ingress of mud,dirt, grit and the .like, and they control the feed and distribution ofthe lubricant which is supplied to the bearing surfaces 58. 59 and 60and to the parts of the blade which move relative to each other. Inorder to provide for the lubrication referred to the shank 53 is formedwith a lengthwise axial opening 72 which extends from its outer end to apoint adjacent the reduced extension 54 and which constitutes an oilreservoir.

plug 73 closes the outer end of the opening 72. Transverse oil passages74 extend from the axial opening or oil reservoir 72 to the bearingsurfaces 58, 59 and 60. These trans- 74 communicate at their outer endswith spiral oil grooves 75 formed on the bearing surfaces. The blade 50is used in exactly the same manner as the blade 6 except that it thefluid pressure is not capable of holding the blade in horizontalposition in extremely hard rock formations, the action of the fluidpressure may be supplemented by lowering a string of tubing rods or thelike down onto the piston head 14, p

so as to positively force the piston downwardly and consequentlypositively hold the blade 50 in horizontal position.

The reamer constituting the present invention may be readily convertedinto a tool for cutting through and milling away a section of the wellcasing by merely substituting the blade 7 6 shown in Fig. 6 for theblade 6. The

blade 76 is of similar construction to the blade 6 but is shorter, asshown in the drawings. When the casing is set in the bottom of the welland cemented from the bottom so that all production will be shut offboth above and below the pay formation, the pay formation alone may beopened to the casing by reaming out the section of the casing that lieswithin the confines of the pay formation. This can be done by using theshort blades 76 to cut through and mill away the casing within theconfines of the pay formation. This cutting away and milling isaccomplished by rotating the tool in one position until the blade opensand then by slowly reaming or milling down, the casing will be cut awayby the bottom cut-' ting edge of the short blade until the desiredlength of easing has been removed. The long reaming blade 6 will then beapplied and the balance of the reaming carried out as hereinabovedescribed or if the formation is too hard the blade 50 may be employed.

A tool constituting the present invention may be advantageously used formining oil. The oil industry in this country is beginning to appreciatethe advantages of mining oil. Old oil fields in France and Germany havebeen made to produce four or five times as much as they produced fromwells by sinking shafts and driving tunnels through the oil producingformations. One mode of oil mining has been very well described in anarticle appearing in a ournal or publication.

known as Oil Trade, the article appearing on page 26 of the issue ofFebruary, 1925, Vol. 16. No. 2. A shaft for oil mining may be producedas follows: In-practical operation the ordinary 6 with the usual 4 drillstem can be reamed out to a diameter of three or four feet. Then bygoing into the well with an 8" or 10" drill stem and using a reamingtool of suitable diameter with a blade 3 or 4 feet long a shaft six oreight feet in diameter can be made. Of course, the blade 6 could be usedin soft formations and the blade 50 in very hard'formations.

I claim:

1.' A reamer blade comprising a head, a shank extending from the headhaving a plurality of bearing surfaces of varying diam- 1 eters definingshoulders, a plurality of roller diameter well drilled cutters mountedupon the bearing surfaces 7.

of the shank, said cutters having annular re cesses confronting eachother at the shoulders. acking means situated in said recesses andabutting the shoulders, and means for holding the roller cutters inplace upon the shank.

2. A reamer blade comprising a head, a shank extending therefrom havinga plurality of bearing surfaces of various diameters providingshoulders, a plurality of roller cutters mounted upon the bearingsurfaces. one of said roller cutters abutting the head. said cuttershaving recesses confronting each other at the shoulders. said one of thecutters having a recess adjoining the head, packing means situated inthe various recesses abutting means for holding the cutters in placeupon the shank.

3. A reamer blade comprising a head, a shank extending therefrom beingformed to provide a plurality of bearing surfaces of progressivelyvarying diameter, thus defining shoulders, a plurality of roller cuttersmounted upon the bearing surfaces and having recesses confronting eachother at the shoulders, washers fitted in the recesses and being formedto engage both adjacent bearing surfaces and the shoulders, and meansassociated with the extremity of the shank and with the end cutterlocking the cutters in free-turning position upon the shank.

4. In a rotary reamer -for wells, a hollow the shoulders and headrespectively,and

rotary drill stem, a rotary reamer assembly carried by the lower end ofsaid stem and including a casing having a cylinder therein, a reamerblade pivoted to the cylinder, a piston in the cylinder, motiontransmission means between the piston and the blade for swinging thesame outwardly and upwardly, said piston having a pair of heads and aneck connecting the heads, the upper head having a port affordingcommunication between the hollow drill stem and the space between thepiston heads, said casing having a small escape port controlled by theupper head of the piston and a large escape port controlled by the lowerhead of the piston, the small escape port being adapted to permitdraining of the drill stem and being adapted to supply a certain amountof washing fluid to the reamer blade and the large escape port beingadapted to supply a full amount of washing fluid to the reamer blade.

5. In a reamer blade, a shank of stepped formation, separate rollercutters individually revoluble on the steps of the shank, and meansattached to the shank for immediately holding one of the cutters inplace and so preventing axial displacement of all of the roller cuttersat the end of the shank.

ALEXANDER BOYNTON.

